I have a 1996 plymouth voyager 2.4 engine ( 4 cylinder)   about two weeks ago the van would not start when I would come home during the lunch hour. Only after I kept starting it for about 20 times it would then start. Suddenly now it starts BUT its only running on two pistons! My mechanic checked the coil and found that it is not shooting spark in the number 2 and 3 exits of the coil. I took it to the car electrician and told me that the car computer is bad and it needs replacing! Can you help me?    Ruben